Given equations a and b as 2/5x+y=12 and 5/2y-x=6 respectively which expression will eliminate the variable x a) 5/2a+2/5b b)5/2a-b c) a+ 2/5b d ) 5/2a-2/5b e) 25/10a+6/10b

An observer(o) spots a plane(p) taking off from a local airport and flying at a 29 degree angle horizontal to her line of sight and located directly above a tower(t). the observer also notices a bird circling directly above her. if the distance from the plane(p) to the tower(t) is 6,000ft., how far is the bird(b) from the plane(p).